MJ2001 Amplifier Board MJ11032/33 HiFi Class A Power Amp Board Aluminum Plate*

Description: Description MJ2001 50W Amplifier Board MJ11032/33 HiFi Class A Stereo Power Amp Board Aluminum Plate Heat Conduction Specifications: Maximum output power: 180W / 8 ohms, 350W / 4 ohms Maximum supply voltage: + -60V (main power), speaker protection Power: AC 12V -15V Harmonic Distortion: <0.001% 10W / 8 ohms; <0.05% 100W / 8 ohms Frequency response: 1Hz-200KHz Damping coefficient: > 200 Signal to noise ratio: > 96dB Conversion rate: > 35V /μS Input impedance: 33.2K Gain: 31dB (34x) Features: 1. The circuits at all levels are designed in Class A state (the working state of the output tube is adjustable), which effectively improves the fax degree of the voice. 2. The open loop voltage gain design is relatively low, only more than 60dB, which makes the sound of the power amplifier more realistic and vivid. 3. The output stage adopts inverted Darlington circuit output, which effectively improves temperature stability and reduces distortion. 4. The amplifier part of the power amplifier adopts a set of power supplies, which is convenient to use (the protection circuit needs to be connected to a set of power supplies). 5. There is a complete protection circuit, with over-current, output short-circuit and DC protection functions, using original American TE Tyco high-quality relays. Using 3 high-current relays per channel can better over-current, but also effectively extend the life of the relay. 6. The power input and signal output of the power amplifier use standard connectors, which can be connected by 6.3mm plug springs without welding, very convenient. 7. The power amplifier adopts high-precision and stable DALE resistors. 8. Low distortion rate, good thermal stability. Wiring diagram and debugging method: Mid-point voltage test: The mid-point voltage of this board is free of adjustment. In a static state, no signal is input, and the DC voltage at the output terminal is measured. If it is normal, it is below 50mv, as shown in the following figure: Static current debugging: connect the black meter pen to the signal output terminal, and the red meter pen to measure the C pole of the power tube, which is the outer shell of the power tube. The measured voltage is the voltage of the non-inductive resistance, and then converted into current according to Ohm's law. Please make adjustments according to actual usage. The higher the voltage, the greater the quiescent current, the greater the heat generation, and vice versa. This is only for testing. Please add a heat sink during actual use. The connecting aluminum plate is far from enough for heat dissipation. The quiescent current test result in the figure below: 249.6MV÷0.5Ω (two 1 ohms in parallel, ≈500MA, the total quiescent current of the power tube is 1A. Package List: 1 Pair of Amplifier Board Payment Terms 1.We accept PayPal only. 2.All major credit cards are accepted through secure payment processor PayPal. 3.Payment must be received within 7 business days of auction closing. 4.We ship to your eBay or Paypal address. Please make sure your eBay and Paypal address is correct before you pay. Shipping Terms - For remote regions, we will charge your extra shipping costs. Usually it cost about 35USD-50USD. We will contact you after your payment. Thanks for your understanding. Return Terms 1. If you receive defective item, please kindly notify us within 14 days. We will guide you the returning instruction for replacement or refund. 2. If you purchased in improper condition, please NOTE that the sipping and handling fee will not be refund, all return shipping fee should paid by the buyer unless item DOA. 3. We reserve the right to refuse any returns for objective reasons. Custom Duties & Taxes 1. Import duties, taxes, and charges are not included in the item price or postage cost. These charges are the buyer's responsibility. 2. Avoiding some unnecessary trouble, please check with your country's customs office to inform us what we should declare its value before shipping. Feedback 1. If you are dissatisfied for any reason, please don't be quick to leave us neutral or negative feedback. We work hard to make sure EVERY CUSTOMER 100% SATISFIED and resolve any problem for you and always leave positive feedback to all our customers. 2. If you are satisfied with the product you received, please kindly leave us a positive feedback and 5 star DSR. If there is any problem of your order, please feel free to contact us firstly, we are responsible and credible seller, will follow it for you asap. On Feb-19-21 at 19:38:15 PST, seller added the following information:

Price: 208.94 USD

Location: Shenzhen

End Time: 2024-08-20T02:31:49.000Z

Shipping Cost: 2.99 USD